AMC Eagle Den Forum

The Mighty 258 => The Engine => Topic started by: ammachine390 on December 21, 2012, 06:13:41 PM

Title: Engine Vibration
Post by: ammachine390 on December 21, 2012, 06:13:41 PM
My Concord has what I believe to be an engine vibration. Whenever the engine hits a certain rpm, the car shakes. I can feel it in the steering wheel, and the whole car shakes. It happens most when cruising at 40 mph, if I let off the gas and let the rpms drop, vibration goes away. If I downshift to second, the rpms increase and I stay at 40 mph, then the shaking stops. So I believe it is completely dependent on engine speed. I'm leaning toward a bad harmonic balancer. Sound right? Any other ideas?
Title: Re: Engine Vibration
Post by: amcinstaller on December 21, 2012, 06:32:48 PM
is this the same car you had the squealing with? or am i totally out to lunch on that one?
Title: Re: Engine Vibration
Post by: ammachine390 on December 21, 2012, 08:14:04 PM
Quote from: amcinstaller on December 21, 2012, 06:32:48 PM
is this the same car you had the squealing with? or am i totally out to lunch on that one?
Good memory, it is the same car. However, the squealing likes to come and go.
Title: Re: Engine Vibration
Post by: ammachine390 on December 21, 2012, 10:55:37 PM
It does seem to vibrate at idle a little more than it should, at least more than it used to. Will have to try revving it up.
Title: Re: Engine Vibration
Post by: BenM on December 23, 2012, 01:35:01 PM
Some easy things to check - look at all six plugs to see if they look the same and check the vacuum line connections above the runner for cylinder 6. I've had vibrations it the past that are just related to that one cylinder running lean, and have had just one plug foul up before.
Title: Re: Engine Vibration
Post by: carnuck on January 13, 2013, 04:43:42 PM
My Eagle did that just before the torque converter died.
Title: Re: Engine Vibration
Post by: A-A EAGLE on January 15, 2013, 04:17:20 PM
Sounds like a faulty torque converter as the shudder appears when the overdrive comes in at approx 40mph....

Anjo
Holland
Title: Re: Engine Vibration
Post by: ammachine390 on January 16, 2013, 03:43:40 PM
Hope it's not the torque converter, transmission was just professionally rebuilt in August.
Title: Re: Engine Vibration
Post by: amcinstaller on January 16, 2013, 06:24:40 PM
if you put the car in park or neutral can you replicate the noise